1. Field of the Invention
This invention relates to a video camera which is particularly used with video recorders.
2. Description of the Prior Art
Video recording systems including, in combination, a video camera and a video recorder are being broadly utilized.
Among such video recording systems, most video recording systems of simple type utilizing, for example, a cassette type video recorder are so arranged that all circuits in the camera are energized by a power supply in the recorder or other external power supply when the camera is operatively connected with the recorder or when a power switch in the recorder is turned on in the connection of the camera with the recorder or when a recording button is further turned on under the turning on of the power switch. Thus, the camera is in operation and the recorder is set at its standby state for recording. Under such a situation, when a trigger button in the camera is turned on, a recording start signal is fed from the camera to the recorder to initiate the operation of the latter so that any video output from the camera will be recorded on a video tape in the recorder. This is due to the fact that an image pick-up tube in the camera must be heated to its normal operation temperature, that is, to such a condition as to generate appropriate image scanning signals for a very long time period such as about ten seconds. However, such very long time period for heating is required only by the heater circuit in the image pick-up tube but not by the other circuits in the same. In the entire camera, the heater circuit for the image pick-up tube has about 20% of electric power consumption while about 80% of the electric power consumption is shared by the other camera circuits. The energization of all circuits in the camera, for example, when the recorder is set at its standby state for recording provides substantial loss in electric energy in the camera. This is disadvantageous particularly in portable video systems having limited capacity of electric energy.